Unable to Connect - SQL Server or Network Problem?

Applicability:

SQL Server 2000: Tested

SQL Server 2005: Tested

SQL Server 2008: Tested

SQL Server 2008R2: Tested

SQL Server 2012: Tested

Credits:

Author: Unknown

Date: 7 May 2012

Description

Close behind the popular "it worked on my workstation" statement from developers, comes the "I can't connect to the SQL Server" statement, although sometimes this can come from the user community as well.

I've lost count of how many times I've investigated this one, and how many times I've tried to think how I might easily determine that it is not a SQL Server configuration problem.

I ran across this little gem several weeks ago - and like all gems, you wished you'd found it years ago. Hindsight shows this is mostly common sense, but it's so easy not to see these things.

Anyway, the folowing illustration demonstrates how quickly is can be fairly reliably determined whether the problem lies within SQL Server or within the Network.

Code